Friedbich pichleb



F. PICHLER WALL FOR VESS EIQS SUBJECTED T0 EXTERIOR OVERPRESSURE March 2 1926. I 1,575,226

Fild Jan. 25, 1924 Friedrich Flt-h \NVE NTO Rf By MAM/z Patented Mar. 2, 1926.

UNITED STATES PATENT OFFICE.

FRIEDRICH PICHLER, OF INGOLSTADT, GERMANY.

WALL FOR VESSELS SUBJECTED T EXTERIOR OVEBPRESSURE.

Application filed January 25, 1924; Serial No. 688,628.

To all whom it may concern: 7 is intended. The joining of the individual Be it known that I, FRIEDRICH PIGHLER, wall units can be accomplished by rivetting citizen of Germany, residing at Ingolstadt, or the like with the help of stiffening Bavaria, Germany, have invented certain rings (Z2). new and useful Improvements in Walls for hat I claim as my invention and desire Vessels Subjected to Exterior Overpressure to secure by Letters Patent is: (for which an application was filed in Gen 1. As a new article of manufacture, a thin many March 23, 1922); and I do hereby wall for vessels subject to heavy external declare the following to be a full, clear, and pressures, said wall consisting of a series exact description of the invention, such as of juxtaposed curved. units, the outer surface 5 will enable others skilled in the art to which of each unit presenting an uninterrupted it appertains to make and use the same. concave curvature only and the total area of According to the present invention the the juxtaposed parts of the units being so ails of vessels subjected to exterior overminute as compared with the area of the pressure are so shaped that their individual curved portions that the major portions of on parts are subjected only to tensile forces the wall constituted by the part of concave and can therefore be made as thin as possible, curvature are subjected only to tensile thereby achieving considerable economy in stresses and the relatively minute portions constructive material and greatly reducing of the wall at which the units are juxtaposed the weight of' the vessel. are subjected to compressive strains within 1" To this end the walls of the vessel are the material of the wall upon the occurrence composed of separate units with trough or of asubstantial exterior pressure. groove-shaped outer surfaces, of which the 2. As a new article of manufacture, a semi-circular section is formed with a parwall for vessels subject to heavy external 2 ticular radius found by calculation. pressures, said wall consisting of a series of 70 The accompanying drawing shows a part juxtaposed curved units the wall thickness of a vessel accor-diiw to the present invenof which is from 0.01 millimeter to 3 miltion with a, for example, cylindrical form. limeters, the outer surface of each unit The walls of this vessel consist of open presenting an uninterrupted concave curvaannular units (a) of thin material, of which ture only, the radius of which curvature is 7 the circumference is semicircular in section. from millimeters to 2000 millimeters, the This semicircular shape of the circumference total area of the juxtaposed parts of the results in the material of the walls being units being so minute as compared with the subjected only to tensile forces by the exarea of the curved portions that the major terior over-pressure on the vessel. This portions of the wall constituted by the parts so again makes it possible to construct the of concave curvature are subjected only to walls as thin as is consistent with the greattensile stresses and the relatively minute porcst overpressure to be expected, thereby tions of the wall at which the units are juxreducing the total weight of the vessel as taposed are subjected to compressive strains much as possible. The radius of the within the material of the wall upon the groove or trough-shaped circumference of occurrence of a substantial exterior presthe wall units is in each case chosen or calsure. culated in accordance with the pressure In testimony whereof I hereunto affix my which the vessel is destined for and aocordsignature. 4 ing to the sphere of use for which the vessel FRIEDRICH PICHLER. 

